The present invention relates to a manufacturing management method in a semiconductor device production system, production management apparatus, or apparatus for manufacture of a production management apparatus, and, more particularly, relates to a production management method and apparatus in a production system for semiconductor devices which can greatly improve production efficiency while reducing the switching frequency of processing by manufacturing apparatus in parallel.
In production systems for semiconductor devices, there are those where a plural number of manufacturing apparatus are provided in parallel, so as to enable the processing of a plural number of types of semiconductor products, and a plural number of product groups for manufacture next are in standby, for the next product standby portion, so that when there is a manufacturing apparatus that can process the next products, a production management apparatus, that includes a computer, performs start scheduling for those next products so that a manufacturing apparatus that can perform processing for that next product starts manufacture for one next product standby group from a plural number of product standby groups.
In this type of production system, the start scheduling is generally performed as real time scheduling in accordance with production completion reports from each manufacturing apparatus.
FIG. 1 shows a time series processing system for the manufacture of semiconductor devices.
In this figure, first. T represents the time axis. Downward indication represents the future while reported indicator represents the past.
The apparatuses 1, 2, . . . , n are apparatus for the assembly of semiconductor devices. Each configure a single production line that is incorporated into the production system, and each perform the same processing, for a plural number of types of semiconductor products as described above, through the switching of jigs and tools and their setting up. Furthermore, these apparatuses 1, 2, . . . , n have a production completion information function, as shown as the flowchart of FIG. 2. This is to say that the apparatuses 1, 2, . . . , n check for whether or not production is completed for all of the group of products that has been started in step ST801, and when production is completed, production completion information is sent to a host computer in ST802, with transmission in the direction of the production management apparatus.
Symbols p1-p6 show the product group, and A-D show the types of each of the corresponding product groups p1-p6. Accordingly, the product type of the product group p1 is A, the product type of the product groups p2 and p3 is B, the product type of the product group p4 and p5 is C, and the product type of the product group p6 is D.
The solid line L.sub.11 shows when the apparatus 1 handles the product group p1, the broken line L.sub.12 shows when the apparatus 1 handles the product group p2, the solid line L.sub.21 shows when the apparatus 2 handles the product group p3, the broken line L.sub.22 shows when the apparatus 2 handles the product group p4, the solid line L.sub.31 shows when the apparatus 3 handles the product group p5, and the broken line L.sub.32 shows when the apparatus 3 handles the product group p6.
The apparatus 1, 2, . . . , n outputs completion information to the production management apparatus, when there is completion of processing for a single product group, and f1, f2, . . . , fn are the production completion informations that are output by each apparatus 1, 2, . . . , n.
Symbols s are product shelves for a plurality of next start standby product groups (in other words, a buffer). A single product group contains a plural number of products of the same type, which are started to each of the apparatus 1, 2, . . . , n in the status where they are still contained in storage boxes.
The following is a description of the scheduling by a production management apparatus of a production system as described above.
First, at a time prior to the time t71, the apparatus 1 performs assembly processing for the product group p1, the apparatus 2 performs assembly processing for the product group p3, and the apparatus n performs respective assembly processing for the product group p5.
Then, when the apparatus 1 has completed the processing for the product group p1, the production completion information f1 is given to the production management apparatus at the time t71.
When this occurs, the production management apparatus that receives it determines the next product that is to be started by the apparatus 1, from the start standby product groups that are on standby in the shelves s. This is performed in accordance with predetermined priority rules. These priority rules take FIFO (first-in-first-out) as the premise, and when the shelves s have no product groups of the same type as the product group that was being processed by the apparatus that gave the production completion information, the oldest of the next start standby product groups is determined as the next start product, and when the shelves s have a product group of the same type as the product group that was being processed by the apparatus that gave the production completion information, then that is given priority and the start standby product group of the same time is determined as the next start standby product group. Here, there are only the three product groups p2, p4, p6 on the shelves s shown in the figure, and the order of priority is determined as p2, p4, p6 in accordance with the FIFO rule. Accordingly, in this case, when the next start product is determined, the production management apparatus gives the start instruction so that the product p2 is pulled in the direction of the apparatus 1. In this case, the set-up change instruction accompanies the product change.
With this, the product p2 is started by the apparatus 1.
In the same manner, at the time t72, the production completion information f2 is given from the apparatus 2 to the management apparatus for the product p3 of the same type B, but even at this time, there is no product of the same type since the product of the same type B has already been started to the apparatus 1 and so the product C is started to the apparatus 2 in accordance with the FIFO rule.
Furthermore, at the time t73, the production completion information fn is given from the apparatus N to the management apparatus for the product p5 of the same type C. But even at this time, there is no product of the same type, since the product of the same type C has already been started by the apparatus 2. So, the product D is started by apparatus n in accordance with the FIFO rule.
In this manner, the product groups on standby in the shelves s are successively started by empty machines by a scheduling of the product management apparatus and production is implemented.
However, when there is switching of the processing type for the same apparatus, a set-up change is performed when there is the start of the product group as described above but with a conventional production management method as described above, there are cases where the processing product is switched even though such switching of the processing product would not be necessary if there were a short wait time, i.e., an increase in the number of times of changing the setting-up.
At the time t71, there is the start of the product group by the apparatus 1, and that at the time t72, there is the start of the product group p4 by the apparatus 2.
It requires time and trouble to change the setting-up in a production system and the production period becomes longer for unnecessary changes of the setting-up. This creates increased loads on the workers.
As has been described above, in a conventional production system, there is therefore this problem of an increase in the frequency of unnecessary changing of the processing product.